Yellow-orange part of brooch replaced (5)
I believe the answer is:
ochre
'yellow-orange' is the definition.
(I've seen this before)
'part of brooch replaced' is the wordplay.
'part of' indicates the answer is hidden within the clue.
'OCHRE' is hidden within 'brooch replaced'.
(Other definitions for ochre that I've seen before include "Light yellow-brown colour" , "Earthy pigment - light brownish-yellow" , "yellowy-orange" , "A shade" , "Chore (anag) - pale brownish-yellow" .)